From: tag@nrlmry.navy.mil Date: Fri, 08 Jul 94 16:32:21 pst Name: Paul M. Tag Organization: Naval Research Laboratory Interests: AI Applications to Navy Needs NRL Monterey conducts meteorological research for the Navy and has been involved in AI since about 1987. Our efforts have included expert system development for overwater fog prediction (see Peak and Tag, Monthly Weather Review, 1989, 2641-2653), tropical cyclone movement (Buck Sampson), satellite imagery interpretation (see below), and clear air turbulence forecasting (Jim Peak); next year we plan to develop an expert system addressing Navy weather concerns in the Mediterranean (Richard Bankert and Arunas Kuciauskas). Neural network use here has addressed satellite imagery interpretation (see below) and cloud classification from satellite imagery (see Bankert, Journal of Applied Meteorology, 1994 (just coming out)). Of particular interest may be Rich Bankert's work with a Probabilistic Neural Network (PNN). The PNN is a NN architecture for direct solution of the Bayesian classification rules. It allows for quick training without sacrifice in accuracy when compared to more common feed-forward back-propagation networks. Jim Peak has worked on a number of components of our satellite imagery interpretation project and has linked them together into a simple working prototype. Our goal is to completely automate the meteorological interpretation of cloud patterns visible in satellite imagery. We have put the meteorological expertise to do the interpretation into an expert system, but the pattern recognition, etc. is the hard part. We have addressed the segmentation problem with a new NN-based approach. Rich Bankert has developed a routine to identify segmented cloud patterns (fronts, cells, jet cirrus, etc.) using shape, size, texture, and spectral features within a neural network. One thing he is lacking to test it is expertly labeled data. If anyone wants to help in this regard, please contact him. Feature analysis, following segmentation and identification, is accomplished using empirical orthogonal functions and neural nets. Our overall design for the imagery interpretation is summarized in two papers: Peak and Tag, Bulletin of the American Meteorological Society, 1992, 995-1008 and Journal of Applied Meteorology, 1994, 605-616. Recently, I have tried testing machine learning methods to determine their applicability to meteorological problems. In particular, we are using Quinlan's C4.5 program as applied to fog prediction. Using the data base we used in developing the fog expert system, we are determining whether C4.5 can generate the prediction rules that we already know. A similar study involves using buoy data off the coast of California. If there are meteorological data sets out there in which each case has both related predictors (as many as considered important) and definite outcomes, and if the data set is coastal or open-water oriented, I would like to know about them. Coming up with good data sets addressing meteorological parameters of interest to the Navy is more difficult than I envisioned. If anyone needs copies of our papers or if there is any interest in (or help for) our work, our e-mail addresses are as follows: bankert@nrlmry.navy.mil kuciauskas@nrlmry.navy.mil peak@nrlmry.navy.mil sampson@nrlmry.navy.mil tag@nrlmry.navy.mil Paul M. Tag Naval Research Laboratory 7 Grace Hopper Avenue Stop 2 Monterey, CA 93943-5502 U.S.A. (408) 656-4885 Fax: (408) 656-4769